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January 20, 2021 [Issue 21561] Unsafe aliasing of immutable union member allowed in @safe code | ||||
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 | https://issues.dlang.org/show_bug.cgi?id=21561 Paul Backus <snarwin+bugzilla@gmail.com> changed: What |Removed |Added ---------------------------------------------------------------------------- Keywords| |safe -- | |||
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ReplyJanuary 20, 2021 [Issue 21561] Unsafe aliasing of immutable union member allowed in @safe code | ||||
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 | https://issues.dlang.org/show_bug.cgi?id=21561 Chloé <chloekek@use.startmail.com> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |chloekek@use.startmail.com --- Comment #1 from Chloé <chloekek@use.startmail.com> --- Note that assigning to the a.x is still prohibited: --- Error: field `U.x` cannot modify fields in `@safe` code that overlap fields with other storage classes --- With that in place, is it necessary to also prohibit accessing the field? -- | |||
January 20, 2021 [Issue 21561] Unsafe aliasing of immutable union member allowed in @safe code | ||||
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 | https://issues.dlang.org/show_bug.cgi?id=21561 Bolpat <qs.il.paperinik@gmail.com> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |qs.il.paperinik@gmail.com Hardware|x86_64 |All OS|Linux |All -- | |||
January 20, 2021 [Issue 21561] Unsafe aliasing of immutable union member allowed in @safe code | ||||
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| https://issues.dlang.org/show_bug.cgi?id=21561 --- Comment #2 from Paul Backus <snarwin+bugzilla@gmail.com> --- Yes, because the data can still be modified by assigning a new value to the whole union. --- void oops() { U a = { y: 0 }; U b = { x: 1 }; assert(a.y == 0); a = b; assert(a.y == 1); } --- Strictly speaking, the problem is that we are allowed to access a.y after its lifetime has ended. However, this only leads to undefined behavior when unsafe aliasing is involved, so the unsafe aliasing is what needs to be fixed. -- | |||
February 27, 2021 [Issue 21561] Unsafe aliasing of immutable union member allowed in @safe code | ||||
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 | https://issues.dlang.org/show_bug.cgi?id=21561 anonymous4 <dfj1esp02@sneakemail.com> changed: What |Removed |Added ---------------------------------------------------------------------------- See Also| |https://issues.dlang.org/sh | |ow_bug.cgi?id=19916 -- | |||
February 27, 2021 [Issue 21561] Unsafe aliasing of immutable union member allowed in @safe code | ||||
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| https://issues.dlang.org/show_bug.cgi?id=21561 anonymous4 <dfj1esp02@sneakemail.com> changed: What |Removed |Added ---------------------------------------------------------------------------- Blocks| |19916 See Also|https://issues.dlang.org/sh | |ow_bug.cgi?id=19916 | Referenced Issues: https://issues.dlang.org/show_bug.cgi?id=19916 [Issue 19916] union member access should be un-@safe -- | |||
December 17, 2022 [Issue 21561] Unsafe aliasing of immutable union member allowed in @safe code | ||||
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 | https://issues.dlang.org/show_bug.cgi?id=21561 Iain Buclaw <ibuclaw@gdcproject.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Priority|P1 |P3 -- | |||
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